In your lifetime, your kidneys filter more than one million gallons of water, enough to fill a small lake. Amazingly, one kidney can handle the task perfectly well. In fact, if you lose a kidney, your remaining kidney can increase in size by 50 percent within two months, to take over the job of both.3
Urine is 95 percent water and five percent urea, uric acid, minerals, salts, enzymes, and various substances that would cause problems if allowed to accumulate in your body4. Normal urine is clear and has a straw yellow color, caused by a bile pigment called urobilin.
As with your stool, your urine changes color depending on what foods you eat, what medications and supplements you take, how much water you drink, how active you are, and the time of the day.
But some diseases can also change the color and other characteristics of your urine, so it’s important to be alert and informed. With so many variables, you can’t always be sure of what’s causing any particular urine characteristic, short of laboratory testing. However, urine’s character gives you some clues to potential problems that may be developing, giving you time to do something about it.
The following chart outlines some of the most common color variations for urine and their possible origins. The majority of the time, color changes resulting from foods, medications, supplements, or simply dehydration. But there are certain signs that warrant concern.
Color Possible Cause Necessary Action Yellow/Gold The most typical urine color, indicative of a healthy urinary tract; yellow will intensify depending on hydration; some B vitamins cause bright yellow urine None Red/Pink Hematuria (fresh blood in the urine) related to urinary tract infection (UTI), kidney stone, or rarely cancer; consumption of red foods such as beets, blueberries, red food dyes, rhubarb; iron supplements; Pepto-Bismol, Maalox, and a variety of other drugs5; classic “port wine” color may indicate porphyria (genetic disorder) ***Consult your physician immediately if you suspect you have blood in your urine White/Colorless Excessive hydration is most likely. (See Cloudy) Consult your physician only if chronic Orange Typically a sign of dehydration, showing up earlier than thirst; “holding your bladder” for too long; post-exercise; consuming orange foods (carrots, squash, or food dyes); the drug Pyridium (phenazopyridine); liver or pituitary problem (ADH, or antidiuretic hormone) Drink more water and don’t delay urination; consult physician if orange urine persists despite adequate hydration Amber More concentrated than orange so severe dehydration related to intense exercise or heat; excess caffeine or salt; hematuria; decreased urine production (oliguria or anuria); metabolic problem; pituitary problem (ADH, or antidiuretic hormone) Consult your physician if problem persists despite adequate hydration Brown Very dense urine concentration, extreme dehydration; consumption of fava beans; melanuria (too many particles in urine); UTI; kidney stone; kidney tumor or blood clot; Addison’s disease; glycosuria; renal artery stenosis; proteinuria; pituitary problem (ADH, or antidiuretic hormone) Consult your physician if problem persists despite adequate hydration, especially if accompanied by pale stools or yellow skin or eyes Black RARE: Alkaptonuria, a genetic disorder of phenylalanine and tyrosine metabolism marked by accumulation of homogentisic acid in the blood; poisoning Consult your physician Green RARE: Unusual UTIs and certain foods (such as asparagus); excessive vitamins Usually benign; consult your physician if it persists, especially if you have pain or burning (dysuria), and/or frequent urination (polyuria), which are symptoms of UTI Blue RARE: Artificial colors in foods or drugs; bilirubin; medications such as methylene blue; unusual UTIs Usually benign; consult your physician if it persists, especially if you have pain or burning (dysuria), and/or frequent urination (polyuria), which are symptoms of UTI Cloudy Urinary tract infection, kidney problem, metabolic problem, or chyluria (lymph fluid in the urine), phosphaturia (phosphate crystals), pituitary problem (ADH, or antidiuretic hormone) Consult physician, especially if you have pain or burning (dysuria), and/or frequent urination (polyuria), which are symptoms of UTI Sediment Proteinuria (protein particles) or albuminuria; UTI; kidney stones; see Cloudy Consult your physician Foamy Turbulent urine stream; proteinuria (most common causes are diabetes and hypertension) Consult physician if not due to “turbulence”